Contact printer



Feb. 18, 1969 G. R. ANDERSON ET AL 3,428,400

CONTACT PRINTER Filed March 10, 1967 v INVENTORS H 645mm flzvaiksafl JOHNA'.$VE/Y0.$'E/Y United States Patent 3 Claims ABSTRACT OF THE DISCLOSURE A toy copy-machine comprises a light exposure station and a heat development station in side-'by-side elationship with a flexible pressure-curtain mounted between them for pressing the sensitive sheet materials against either station as required.

This invention relates to the copying of printed matter or the like, and in particular to copying apparatus of maximum simplicity both in construction and in operation and which is therefore suitable for use as a toy.

Copying apparatus is known for use in the copying of documents by a process involving exposure of the document to light through a light-sensitive intermediate sheet followed by heating the exposed intermediate in contact with a receptor or copy sheet. The present invention likewise provides an apparatus including both lightexposure and heat-exposure stations but characterized by extreme simplicity and low cost. At the same time the apparatus is fully self-contained and may be operated with complete safety and with essentially no previous training, making it ideal as a toy for children as well as an instructive and useful copying machine for adults.

A preferred form of the apparatus is illustrated in the accompanying drawing, in which FIGURE 1 is a view in perspective,

FIGURE 2 is a top plan view with the arcuate top panels and pressure screen removed, and

FIGURE 3 is a front elevation in section taken along vertical plane 3--3 of FIGURE 1.

As illustrated in FIGURE 1, the apparatus includes a light chamber having a light-transmissive elongate laterally areuate cover 11, a heat chamber having a heatconductive elongate laterally areuate cover 12, and a thin flexible transparent pressure cover 13, all joined together along a common straight edge. The two chambers are enclosed by side walls 14 and 15, end walls 16 and 17, and central partition 18, all supported on a common base 19, as further indicate-d in FIGURES 2 and 3.

A source of heat, represented as electrical resistance wire 20 strung on asbestos board panel 21, is supported between side wall 14 and central partition 18 just beneath the heat-conductive cover 12 by means of suitable clamps. A source of light, represented as bulb 22 in socket 23, is supported from the opposite face of the partition 18 at the lower center of the light-chamber beneath the light-transmissive cover 11.

An electrical cord 24 with plug 25 is provided for attachment to a source of electrical energy. The cord connects to the heater element 20 through a thermostat 26 mounted on the end wall 17 just beneath the cover 12. The cord is also connected through a switch 27 to the socket 23 and bulb 22, and directly to a pilot light 28, both switch and pilot light being mounted for convenience on front end wall 16.

The presure cover 13 is hemmed along one side to form a narrow loop fitting over a rod 29 held at its ends in braces 30 and 31. The rod is desirably provided with a loop or other handle portion at the front end and is threaded at the rear end for rention within the correspondingly threaded brace 31. The enclosed rod fits tightly between the outer faces of the covers 11 and 12 and assists in retaining the covers within the channel provided for the purpose along the upper edge of the partition 18. Thus the flexible cover 13 and the two rigid covers 11 and 12 are joined together along a common straight edge.

A rigid handle member 32, which may for example be a wooden dowel, is fastened to the outer edge of the pres sure cover 13 so that the cover may be drawn taut over either of the arcuate covers 11 or 12.

The cover 12 is shown in FIGURES 3 to comprise an inner metal panel 33 and a thin fibrous outer covering 34. Desirably, the outer covering may consist of short fibrous floc bonded to the metal surface with a heat-resistant adhesive; but a thin fabric covering may alternatively be used. Although optional, the fibrous covering is desirable since it assists in equalizing the temperature over the cover area and is particularly valuable as insulation against accidental direct and painful contact with the hot metal panel 33 by the user.

The covers 12 and 11 rest at their outer edges in channels provided for the purpose along the upper edges of side walls 14 and 15, and may be removably anchored therein by screws or other fastening means.

In a representative apparatus, the base, walls and central portion are for convenience made of 41-inch opaque panels of Plexiglas methyl methacrylate polymer, although other opaque rigid materials, eg sheet metal or fiber board may equally well be used. The light-transmissive cover 11 is of Aa-inch clear transparent Plexiglas, and the heat-conductive cover 12 is of thin sheet aluminum covered with thin woven fabric; both covers are arcuately formed, e.g. on a radius of at least approximately four inches and preferably considerably greater, and are about ten inches long and eight inches wide. The pressure cover 13 is of thin, light weight, open mesh nylon bolting cloth or similar screen-like fabric. The heater element consists of seven feet of Nichrome resistance wire having a resistance of 3.2 ohms/foot. A No. 1 Photoflood lamp is employed as the light source.

One method of using the apparatus will now be briefly described. The device is first connected to a source of electricity, in this case at 1'15 volts A.C., causing the pilot light to glow and the heating element to bring the temperature of the cover 12 to approximately 230 F. A sheet of light-sensitive intermediate material is laid over the cover 11 and over it is placed a magazine clipping, sheet of correspondence, sketch or other graphic original of which a copy is desired, with the printed surface in contact with the intermediate. The pressure cover 13 is then drawn taut and lowered smoothly over the original, holding the composite in close uniform contact with the arcuate supporting surface, and the light is turned on by means of the switch 27 for an appropriate length of time. A sheet of receptor copy-paper is then placed on the cover 12, the reflex-exposed intermediate is recovered and laid over the copy-paper, and the pressure cover is again drawn taut and smoothly lowered over the new composite. As the copy is developed on the copy-sheet it becomes visible through the transparent pressure cover and the translucent intermediate, so that pressure may be released and the composite removed as soon as image development has been achieved.

In many instances a copy is desired of only a restricted central area; and the apparatus is fully effective for such applications as desired. Where larger areas must be copied, is is convenient temporarily to release the tension on the pressure cover and move the composite to bring less fully developed areas over the generally more highly heated central area of the cover 12 until full development of all areas is accomplished.

Somewhat improved results in terms of uniformity of light exposure may be obtained by suitably reflectorizing part or all of the interior of the light-chamber, as for example by inserting a sheet of aluminum foil beneath the bulb 22 and positioning the foil to provide maximum uniformity over the exposure surface. Improvement may also be achieved, by placing over the clear plastic surface a thin light-diffusing film, e.g. of polypropylene pigmented with calcium carbonate, or by providing a diffusing surface on the plastic cover itself.

Suitable light-sensitive intermediate and reactive image receptor copy-sheet materials for use in the apparatus of the present invention have been described in U.S. Patent No. 3,094,417.

What is claimed is as follows:

1. Apparatus comprising, in combination: an exposure station including a source of light and an elongate laterally arcuate light-transmissive cover member; a heating station including a source of heat and an elongate laterally arcuate heat-conductive cover member; and a thin flexible transparent pressure cover of a size and shape adapted for fitting over each of said cover members; said pressure cover and said cover members being joined together along a common straight edge.

2. The apparatus of claim 1 wherein said arcuate cover members are in side-by-side generally horizontal position above a central vertical panel separating the light source area and the heat source area.

3. The apparatus of claim 2 including a supporting base, side and end Walls extending from said base to the outer edges of said cover members and, together with said central panel, enclosing said light source in a lightchamber and said heat source in a heat chamber, and control means mounted within said heat-chamber for regulating the temperature at said heat-conductive cover member.

References Cited UNITED STATES PATENTS 2,324,121 7/1943 Tuttle et a1. 9s 73 2,492,476 12/1949 Harvey --73 3,087,402 4/1963 Hamlin 9s-73 3,318,219 5/1967 Anderson 95-73 FOREIGN PATENTS 1,085,093 10/1955 'France.

NORTON ANSHER, Primary Examiner.

CHARLES B. FUNK, Assistant Examiner. 

